Husqvarna rancher 55 leaking fuel

I have a 1999 Husqvarna rancher 55 that started having problems last summer (June 08) The wife noticed gas fumes in the garage (where I store the saw) after I finished cutting some wood (I am guessing I went through a tank or two). At the time, I didn’t make any connection between the fumes and the chain saw because the saw ran okay.

The next time I used the saw (about a month later) it didn’t seem to work as well at high end (bogging down/missing?). I replaced the spark plug (CJ7Y) and everything worked fine (several tanks of fuel), however, the wife still complained of gas fumes in the garage. This time I noticed some fuel under the saw, so I placed the saw into the shed but still didn’t think anything of it because it was running fine.

The next time I used the saw was about a month ago. As usual it started in 3 pulls and idled fine. However, I couldn’t get any power out of it and it would run at full throttle for a couple of seconds before it started coughing. I figured it was bad fuel or a leak in the line so I replaced the fuel, fuel filter, fuel line, and spark plug with no luck.

I took the saw to the local home and garden store that sells and repairs Husqvarnas. After two weeks, they provided me with a $45 bill saying that I had the wrong spark plug (They were the ones that sold me the CJ7Y referred to above) and adjusted the carburetor. As soon as I took my saw out of my vehicle, I knew it wasn’t fixed as there was fuel leakage on the cardboard that I placed the saw on. This time the saw was rough starting (7+ pulls to get it started). After it started, it ran fine for about 5 minutes then it went back to the low power/coughing at full throttle. I was able to do some cutting but it was very slow. I tried opening the fuel cap while cutting (and it seemed to help a little). One point I would like to mention is that the saw seemed to work fine when I was cutting a stump.

I then replaced the fuel cap and fuel vent and still no luck. That is when I noticed fuel leaking from the vent. I removed the vent and put the vent filter in the other way to no avail. It appears as though the fuel is leaking through or around the vent. When I rotate the saw 90 degrees in each direction, fuel drips from the vent and bubbles are visible. There is pressure in the tank as when I open the cap, the fuel is squirted out. I do not have any pressure gauges and will not take it back to the $45 spark plug guy.

I think it is the tank ($120) or the carburetor ($45) not much else left. Any help would be greatly appreciated.

Thanks for the feedback but I already replaced the fuel hose and fuel tank bushing, do you think I might have torn the hose? I don't think that I would still get the gas/air pressure releasing from the gas cap after I shake up the saw if I had a leak in the hose would I?

Did you ever figure this out? I have a similar issue with my 55 Rancher. Starts good but runs inconsistently at power, won't pull consistently in the cuts, and can't keep it tuned. Have ordered a fuel line, will replace that and go after tank vent next if that doesn't work. This is based on reading the site for ideas. Have taken carb apart and cleaned it already to no avail. Carb kit will come next If that doesn't work and no other ideas hit me. Love the saw, and am determined to get this figured out! May even consider some porting work over the winter if I get really motivated - just for fun!

“Did you ever figure this out? I have a similar issue with my 55 Rancher. Starts good but runs inconsistently at power, won't pull consistently in the cuts, and can't keep it tuned. Have ordered a fuel line, will replace that and go after tank vent next if that doesn't work. This is based on reading the site for ideas. Have taken carb apart and cleaned it already to no avail. Carb kit will come next If that doesn't work and no other ideas hit me. Love the saw, and am determined to get this figured out! May even consider some porting work over the winter if I get really motivated - just for fun!

Sounds like an air leak. Pull the muffler and look at the piston before spending too much time. If the piston is scored you will need to start there.

The intake boot and grommet are common places for air leaks on these saws. They are the rubber parts between the cylinder and bulkhead (plastic piece that the carb screws into.) Replace the fuel line too, and make sure it fits tightly against the hole in the tank.

I had read about that, too - thanks. I will take a look at it when/if I get to the point I remove carb again. I have heard that the sealing between the boot and the cylinder can be an issue, too - even if boot isn't cracked. How can that be addressed? New gasket? Sealer? How should boot be reassembled for best sealing? I will pull muffler and check piston and do a compression test, too (should the CT be done cold or hot)? I had thought air leak, too, originally, but after reading thread about the fuel line and vent problems, the running issues sounded similar, so I headed in that direction. I did check the boot to cylinder bolts for tightness and they were good. Oy... What troubleshooting can I do with saw running to differentiate between fuel supply/vent issues and air leak? It starts fine, and after warm up will run well for a while. Then it starts to bog in cut, won't accelerate well, stalls but restarts easily, and so on.

“I had read about that, too - thanks. I will take a look at it when/if I get to the point I remove carb again. I have heard that the sealing between the boot and the cylinder can be an issue, too - even if boot isn't cracked. How can that be addressed? New gasket? Sealer? How should boot be reassembled for best sealing? I will pull muffler and check piston and do a compression test, too (should the CT be done cold or hot)? I had thought air leak, too, originally, but after reading thread about the fuel line and vent problems, the running issues sounded similar, so I headed in that direction. I did check the boot to cylinder bolts for tightness and they were good. Oy... What troubleshooting can I do with saw running to differentiate between fuel supply/vent issues and air leak? It starts fine, and after warm up will run well for a while. Then it starts to bog in cut, won't accelerate well, stalls but restarts easily, and so on.

I've not had a problem getting the boots to seal, but a light coating of Permatex will ensure that it doesn't leak. A light coating is all that's needed, too much will squish out and get sucked into the cylinder.

I believe I put the boot on the cylinder first and then push the bulkhead onto it. You have to make sure that the impulse tube seats into the grommet squarely as well.

The vent on these is on the clutch side just below the carb adjustment holes. There's two screws kitty-corner from each other that need to be removed, then the vent is under that cover. They don't commonly clog though.

Unfortunately an air leak and a bad fuel supply behave similarly. As long as the fuel line is new and not pinched, they usually aren't the problem. Replace the line and filter if in doubt. Compression tests are commonly done with the engine cold, and you need to have a tester with a shrader valve in the tip to get an accurate reading.

Thank you very much. I will have a go at it soon. I ordered the new fuel line and filter, so that will be done first. I'll skip vent and go to carb kit/boot next - might as well do the carb kit while I've got it all torn apart. I have heard that you can troubleshoot vent with gas cap loosened, but that sounds like a recipe for disaster!

Not too hard but requires removing everything before them. Just time consuming.

Quoted from the service manual>
The crankshaft seaIs are accessible after removing the flywheel as instructed in section 6. Ignition System and the oil pump as instructed in section 8. Chain Lubrication System. The seals can be pried out using a suitable screwdriver. Be careful not to scratch or damage the crankshaft during seal removal.
unquote<

Thanks to you both for your assistance. I will pull the muffler and check piston for scoring. If it's Ok, I'll go after the fuel line and maybe even pull the vent - see how it runs. If that doesn't fix it, I'll do the carb and boot. Hopefully, I'll be done at that point. If not, seals are next. Let's hope it's not seals!!

Well, the good news is I pulled the muffler and the piston, rings and cylinder look magnificent from what I could see. No scratches or anything and could still see the hone marks in the cylinder. I am awaiting the fuel line and now need a new muffler gasket. Looking at the muffler it is not clear how to mod it without any welding - the deflector cover is in the way. Right now I am more worried about getting it running right. My next plan is to replace fuel line, filter, rebuild carb and replace intake gasket and boot, and impulse grommet, and possibly the tank vent. If that doesn't do it...